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They are also looking at the stability of the remaining ice shelf, as well as trying to understand how new biological communities might occupy the newly exposed ocean and underlying seabed areas.

The iceberg is about 100 miles long (BAS photo)

Overall, the iceberg is 6,000 sq km in size, and its breaking free is described as a ‘calving’.

Prof David Vaughan, glaciologist and director of science at the BAS, said: “The Larsen A and B ice shelves, which were situated further north on the Antarctic Peninsula, collapsed in 1995 and 2002 respectively. This resulted in the dramatic acceleration of the glaciers behind them, with larger volumes of ice entering the ocean and contributing to sea-level rise. If Larsen C now starts to retreat significantly and eventually collapses, then we will see another contribution to sea level rise.”

The giant iceberg does not pose any immediate risk to the rest of the planet. The ice shelf is a floating extension of land-based glaciers which flow into the ocean, and because they already float, their melting does not directly contribute to sea-level rise.

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But ice shelves act as buttresses holding back glaciers flowing down to the coast, and a BAS spokeswoman said: "In the long term however, we have to watch what happens to the ice shelf behind it, because that is formed from water coming off the glaciers, which in tun act as champagne corks holding back the ice on the continent. If that ice shelf broke up, then that could lead to more ice from the continent flowing into the sea, and that would contribute to sea level rise. However, Larsen C looks like it might behave differently. We have to keep monitoring it closely."

Aerial photo of the iceberg before it broke away (BAS photo)

The 'calving' will allow scientists to carry out new studies of ocean and seabed habitats, to find out what happens to them when the ice shifts so dramatically.

BAS scientists have been debating for a decade with fellow experts at home and abroad what is causing the ice on Larsen Ice Shelf to thin.

A study in 2015 found that between 1998–2012, the ice shelf had lowered by an average of one metre. The study revealed the ice shelf is thinning from both its surface and beneath, suggesting warming air temperatures and warmer ocean currents are play a role.

Prof David Vaughan (BAS image)

Prof Vaughan said: "There is little doubt that climate change is causing ice shelves to disappear in some parts of Antarctica at the moment. We see no obvious signal that climate warming is causing the whole of Antarctica to break up. However, around the Antarctic Peninsula, where we saw several decades of warming through the latter half of the 20th century, we have seen these ice shelves collapsing and ice loss increasing.

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“There are other parts of the Antarctica that which are losing ice to the oceans but those are affected less by atmospheric warming and more by ocean change.

“Larsen C itself might be a result of climate change, but, in other ice shelves we see cracks forming, which we don’t believe have any connection to climate change. For instance on the Brunt Ice Shelf where BAS has its Halley Station, there those cracks are a very different kind which we don’t believe have any connection to climate change.”